Update flake, theme gtk, add vscode cache

Signed-off-by: Nikolaos Karaolidis <nick@karaolidis.com>

hosts/common/scripts/cleanup/cleanup.sh

@@ -20,9 +20,13 @@ mkdir -p /mnt/btrfs
 mount /dev/mapper/luks /mnt/btrfs
 
 if [[ -e /mnt/btrfs/root.bak ]]; then
-  for i in /mnt/btrfs/root.bak/*; do
-    delete_subvolume_recursively "$i"
-  done
+  if [ "$(ls -A /mnt/btrfs/root.bak)" ]; then
+    for i in /mnt/btrfs/root.bak/*; do
+      delete_subvolume_recursively "$i"
+    done
+  else
+    echo "/mnt/btrfs/root.bak is empty. Nothing to delete."
+  fi
 fi
 
 umount /mnt/btrfs